In the emerging world of packet-based communications, packets are increasingly being used to transport content of many types, including streaming media, which needs to be delivered in real time. As new technology, such as wireless local area networks (WLANs) and other access technologies where the transmission path is subject to disturbances, become more prominent, the traditional rules for handling damaged packets may not be applicable for certain types of packet content.
Within the Internet Protocol and other link level protocols, packets having a checksum error, which is indicative of the packet being damaged in any fashion, are immediately discarded. In a wireless WLAN environment, many packets that are damaged may have only a relatively small number of actual bit errors within the packet. If the packet content represents data, such as a bank balance, discarding the damaged packet and requesting a retransmission of the packet is necessary, because retransmission of the packet is the only viable method for assuring that the data is accurately transferred. Further, the delay in receiving the data due to retransmission has minimal if any negative impact on the data transfer.
In contrast, if the damaged packet is transporting streaming media that should be delivered in real time, such as audio, voice, or video, the damaged bits within the packet will certainly have a negative impact, but the impact of a few errant bits may not be catastrophic. Since the data is being used in real time, retransmission is relatively useless, because the order in which the packets arrive and their respective delays are critical in using and delivering the content. As such, there is a need for new techniques in handling packets carrying time-sensitive information wherein data integrity is less important than timely delivery.